The present invention generally relates to a device and a method for generating a filtered activity pattern, to a source divider, to a method for generating a debugged audio signal and to a computer program, in particular to a concept for noise source filtering.
In the field of today's medical technology, it is an important challenge to enable persons with impaired hearing to participate in normal life. For this purpose, from medical technology a great number of different hearing aids are known. It is a special challenge if the inner ear of a patient is damaged. In this case it is necessary to directly excite the auditory nerves of the patient.
Although this may already be successfully achieved with the help of cochlear implants, patients having cochlear implants still have special difficulties when they are close to several different sound sources. In this case, among other things speech intelligibility clearly decreases.
For this reason there is a need to improve the hearing impression of patients with a cochlear implant in particular in situations in which several sound sources are present.
In the following, some documents are discussed which provide background information regarding the mentioned problems.
The article “A revised neurobiologically parameterized model of the cochlea and an attached auditory image processing network” by T. Harczos (a doctorate student in his second year) and his tutor Dr. T. Roska (PPCU Multidisciplinary Doctoral School, 2005-2006 annual report) describes a neurobiologically parameterized model of the cochlea. In the described model, a basilar membrane modeling is used according to an extended Zwicker/Baumgarte model. Further, an inner hair cell is replicated using the model by Meddis, by which a vesicle release is calculated. Further, additionally the synaptic cleft is modeled, and further also processes after the synaptic cleft are modeled.
Further information with regard to a processing of sound data using a Hough transformation are, for example, found in the article “A neurobiologically inspired vowel recognizer using Hough-transform” by T. Harczos, F. Klefenz and A. Kátai (published in the Proceedings VISAPP 2006, Setubal, Portugal, 25-28 Feb. 2006).
The main contribution SCHALLANALYSE with the title “Neuronale Repräsentation des Hörvorgangs als Basis” by G. Szepannek, F. Klefenz and C. Weihs, published online on 28 Sep. 2005, Informatik-Spektrum, Springer-Verlag GmbH, ISSN: 0170-6012 (Paper), describes a modeling of the response of an auditory nerve and an information extraction.
Further information is found in the article “Feature Extraction for sound classification by means of a perceptionally motivated neurophysiologic parameterized auditory model” by T. Harczos, A. Katai, F. Klefenz, P. Schikowski and G. Szepannek (published at the conference of the Gesellschaft für Klassifikation GfKl 2006 from 8 Mar. to 10 Mar. 2006 in Berlin.
Further, the non-prepublished German patent application with the official file number 10 2005 030 326 discloses a concept for analyzing an audio signal. The mentioned patent application, to which, moreover, an international subsequent application with the file number PCT/EP 2005/006315 exists, describes a method and a computer program for analyzing an audio signal to obtain an analysis representation of the audio signal. Further, the mentioned document describes a concept for the neurophysiologically parameterized simulation of the first stages of the auditory system. The teachings and definitions of DE 10 2005 030 326 and PCT/EP 2005/006315 are included by reference herein.
Similarly, the German patent application with the official file number 10 2005 030 327 describes the use of a neurophysiological auditory model and the generation of signals based thereon. With regard to the mentioned document, a parallel US application exists with the official file Ser. No. 11/172,605. The teachings and definitions of the two last mentioned documents are incorporated herein by reference.
Apart from that, U.S. Pat. No. 6,442,510 B1 describes a concept for determining a run-time differential for signal wave forms for a real-time pattern recognition, localization and monitoring of optical and acoustic signals. The mentioned concept includes steps of a segment-wise detection and a bringing into coincidence of signal wave forms for a conversion into monotonous and continuous trajectories for real-time pattern recognition and for the localization and monitoring of optical and acoustic signals. The method described in the mentioned document determines run-time differentials, wherein pre-programmed key signals are detected by signal sampling. Data are corrected by the sampled signals and pairs of signal combinations of given signal run-time differentials are determined from the coincidence of the detected signals.
The device includes at least two receivers for generating sequences of digital values from incoming acoustic signals. The device further includes vector generators to form the digital values in input vectors, a signal detection unit arranged after each vector generator and comprising parallel, programmable signal flow chains and adder/comparator units. The adder/comparator units are arranged vertically to the signal flow chains at equidistant intervals. The device further includes a multi-coincidence unit consisting of two anti-parallel shift registers forming flip-flop chains, and of AND gates.